Refrigerating system



Feb. 5, 1924; 11,482,730 R. A. BURFORD, JR

REFRIGERATING SYSTEM Filed Aug. 26 1922 2.9 30 3 6 Sheets-Sheet 1 FIG.

ATTU P/VEV.

R. A. BURFORD, JR

REFRIGERATING SYSTEM Feh 5, 11924;

.K f 2 J a MQQ Mam e V, Mm WW, 5 m t B e e M 6 v 0 Filed Aug. 26. 1922 Feb. 5, 1924; 1,4827% R. A. BURFORD, JR

REFRIGERATING SYSTEM Filed Aug. 26. 1922 6 Sheets-Sheet 3 A 770/?WE K Feb 5, 1924;

R. A. BURFORD, JR

REFRIGERATING SYSTEM 6 Sheets-Sheet 4 Filed WITNESS.

Feb. 5, 1924; L4$2j3 R. A. BURFORD, JR

REFRIGERATING SYSTEM Filed Aug. 26. 1922 6 Sheets-Sheet 5 l atenterl F 5,

ROBERT A. BURIURID, 3B, OF BIEMING-HMI, ALAJBAEEA.

; RELRIGERATING' SYSILEIE.

application filed August 26, 1922.

To aZZ whom it may concern:

Be it known that 1, ROBERT A. Burro-no, Jr, a citizen of the United States, residing at Birmingham, county of Jefl'erson and State of Alabama, have invented a new and useful Improvement in Refrigerating Systems, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form apart of this specification.

This invention relates to an improvement in refrigerating systems, and more particularly relates to automatic systems of relatively small capacity adaptable for household use.

@ne of the objects of my invention is to provide a system of this character in which the compressor is automatically controlled by the temperature in the storage chamber and the coolin water for the condenser.

A further object of my invention is to provide a compact machine which is so an ranged that all of the parts, With the exception of the expansion coil and the thermostat, are carried on a base which can readily be supported on a refrigerator for family use.

A still further object of my invention is to provide a compressor for the refrigerating medium, which can be operated by a motor requiring a small amount of current, as well as a system in which the flow of -Water for abstracting heat from the condenser can readily be controlled.

Another object of my invention is to provide a simple and efiicient hydraulic motor for actuating the switch for the compressor motor, together with an automatic valve for the hydraulic motor, which is actuated in both directions by the cooling water.

A further object of my invent-ion is to provide a system in which the flow of cooling water is controlled directly by the thermostat, Which in turn starts and stops the compressor motor. The precise nature of my invention will be best understood by reference to the accompanying drawings, which will now be described, it being premised, however, that various changes may be made in the details of construction without departing from the spirit and scope of my invention as defined in the appended claims.

Fig. 1 ,is a plan View of a complete appa- Serial l\:"o. 584,481.

. compressor cylinders.

a 0 1 F Fig. 7 1s a sectional view through the hehd on a diiierent plane from that Fig. 5.

through the compressor ri from that shown in Fig.

Fig. 9 is a horizontal sectional view through the crank case of the com Fig. 10 is a vertical sectional view MlG/Ugll the hydraulic motor for actuating electric switch for the compressor o iving motor.

Fig. 11 is a horizontal sectional view thereof on an irregular line.

Fig. 12 is a diagram illustrating the tire system.

I will first describe the general sy illustrated in Fig. 19;, and later descthe detail mechanism of the various The reference character a designates refrigerating chamber or chamber to cooled. and h a brine tank therein. 0 expansion coil within brine tanlr, d compressor, 6 the condenser, eznaxsion valve, and g a reservoir for renigerating fluid below the compressor,

The compressor dis driven by electric motor it, 'he current for which is controlled by a switch i having switch lever j which is actuated by a hydraulic motor is connected to the water line for cooling the condenser. Z is a thermostat with n to reservoir 9, a pipe p from the res ivc [J to expansion valve which is also connects connected to one end of the condenser and llll which is provided with a suitable shut-d valve, a pipe a connecting theother end of the condenser with hydraulic motor is, a pipe t extending from the motor to thermostat valve m and a ipe w extending from valve m to a suitable waste pipe. to is a pipe extending from the valve mechanism of hydraulic motor is to pipe to for the purpose hereinafter described.

' Assuming the system roperly charged with refrigerating fluid, t e poles of switch i connected to a source of electrical energy and pi e 7" connected to a water supply pipe, with tfie parts set as shown in Fig. 12, there would be no flow of current or water through the system. Under these conditions after the system is inoperation, the temperature in the chamber would be between the maximum and minimum limits. As soon as the temperature rises to the maximum limit, the thermostat I will open valve mand permit water to flow through the water line. As soon as Water starts to flow through the line it will actuate motor a in one direction'an shift lever '53 to close switch 2'. The closing of switch a will close the circuit through motor h, set the motor to rotating, and thereby operate the compressor. The compressor draws the gas from coil 0 through pipe g, compresses the gas and forces it through pipe it, into condenser e, in which heat is extracted by the water passing therethrough. The compressed refrigerating fluid passes as a liquid from the condenser to reservoir through ipe 0, and from which it passes to the expanm'on coil 0 through expansion valve f. The expansion or the fluid from a liquid toa gas in coil 0 will extract heat from the brine, which in turn will cool chamber a. When the temperature in the chamber has been reduced to the minimumpoint, the thermostat Z will permit valve m to be closed by its spring, as hereinafter described, and shut oh? the liovv of water through the symem. This shutting oil of the water will cause the hydraulic motor 7 to shift lever j to open switch a, cut at the current to motor It and thus stop the compressor.

'@ 4 s eaves vided with connecting rods 19 and 20, re-

spectively. The other ends of connecting rods 19 and 20 are connected to gears 21 and 22, respectively, by means of suitable crank pinsx These gears 21 and 22 mesh with each other and are connected to shalts 23 and 2st, respectively.

Shaft 2 1 is journaled in a bearing 25 seated in a bore in casting 11, the outer end of the bore being closed by a screw plug 26.

27 is a similar bearing for shaft 23 in casting 1.1. The shaft 23 is also journaled in a stuffing box in a plug 28, through which the shaft extends. These plugs 26 and 28 seal the ends of said bores and prevent the escape of gas from the crank case.

The outer end of shaft 23 is provided with a driving wheel 29, which is driven by a belt 30 from a small nulley 31 on the shaftof electric motor h. 32 is a belt tightening wheel on the end of a lever 33, pivoted to casting 11, and is arranged to retain the belt in proper driving relation on wheel 29 and pulley 31.

The cylinder head 15 is provided with a gas inlet chamber 34, and 35 are inlet check valves controlling admission ports between chamber 34 and cylinders 13 and 14. These valves are retained in their closed positions by suitable springs surrounding their stems gas to the cylinders-are limited by the upper face of the cylinder casting 12. This is accomplished by so positioning the inlet valve openings that a portion of each is in the plane or its cylinder, while another portion,

thereof is without said plane and is covered by the face of the cylinder castin 12. This limiting of the opening oi the inlet valves will. reduce the escape of gas from the cylinders to the inlet chamber 3 1 when the cranlrs pass the centers and start on thecompression stroke, as the return movement of said valves is relatively short and said valves "Will be immediately seated at the end at the suction strohes.

The pistons 17 and 18 are so connected to the driving mechanism that the cranks till lib

Mill

llli

are opposite to each other so that the pistons move in opposite directions to each other. i

36 is an outlet chamber in the combined cylinder head and valve casing 15 and which is connected to the cylinders 13 and it nesareo by outlet ports, which are controlled by spring-pressed check valves 37. The inlet pipe 9, through which the gas passes to the compressor, opens into chamber 34 and is provided with a shut-0d valve 38. The outlet pipe a is connected to the outlet chamber 86 and the inlet end of the condenser e and is provided with a shutoff valve 40.

The condenser e is formed of an inner tube 41, an outer tube 42 and a continuous piece of wire'43 wound helically about tube 41 and which is substantially in contact throughout its length with the outer face of the inner tube 41 and the inner face of the outer tube 42. The ends of the outer tube 42 are closed by caps through which the inner tube 41 extend. The ends of the outer tube 42 are connected to the ends of pipes 'It and 0, and the refrigerating fluid in its passage through the condenser e from pipe a to pipe 0 is caused to move in a helical manner around and along tube 41 through which the cooling water passes from pipe 7" to pipe 8. By thus forming the condenser of two tubes with a helical wire between them, I am enabled to form a relatively cheap, simple and short condenser having a relatively long contact surface for extracting the heat from the refrigerating fluid.

The hydraulic motor k, which is shown in detail in Figs. 4, 10 and 11, comprises a cylinder 44 with a piston 45 therein, hav ing a stem 46 extending therefrom and which is connected to lever j of switch 2'.

Surrounding stem 46 of piston 45 is a spring 47 which is arranged to move the piston inwardly when the pressure on the front of the piston is relieved by opening the cylinder to exhaust, or if the water supply should fail.

Connected to a cylinder 44 by a port 47 is a cylinder 48 of differential areas. Mounted for reciprocation in cylinder 48 is a piston valve having a head 49 in the large portion of the cylinder and a head 56 of reduced area in the smaller portion of the cylinder. The upper and lower ends of cylinder are connected to each other by a passage 51, and 52 is an adjustable needle valve for controlling the rate of flow of water from one end of cylinder 48 to the other end thereof. The pipe 11, which extends trom hydraulic motor 70 to exhaust or water outlet pipe w from thermostat valve m leads from the cylinder 48 at a point which. is always between the heads 49 and of the piston valve.

The pipe t leads from the larger end of cylinder 48, while pipe 8 from the condenser 0 leads to the smaller end of said cylinder.

The thermostat valve m comprises a casing having an inlet chamber 58 to which the pipe is connected and an outlet chamber 54 to which the pipe 'w is connected. These two chambers 53 and 54 are separated by a septum having a port therethrough which is controlled by a valve 55. 56 is a spring for moving the valve to its closed position and is located in chamber 53, between a head on the valve and an adjustable abutment which is engaged by an adjusting screw 57. The screw 57 extends through a stuffing box 58 in a cap 59 closure for the upper end of chamber 53. The lower end of chamber 54 is closed by means of a cap 60 and a diaphragm 61, there being a gasket interposed between the cap 60 and valve casing to form a tight joint to seal. the lower endot chamber 56, as well as to seal a chamber 62 in the cap 60 below diaphragm 61. The thermostat Z comprises a tube closed at its lower end by means of a plug 63 below a suitable charging valve 64, while the upper end thereof is in communication with chamber 62 in cap 60. The tube of the thermostat Z is charged with an expansible fluid, which expands and contracts as the'temperature of the tube rises and "falls.

Supported on the diaphragm 60 and ar ranged to be moved thereby is a disk 65 having a recess for the reception or" a stem extending downwardly from valve 55.

The various parts of the valve m and thermostat Z are'so arranged that when the thermostat is heated to a predetermined high temperature, the fluid therein will e2;-

pand sufliciently to raise the diaphragm 60 I and raise valve 55 from its seat. This raising of valve 55 trom'its seat will permit the cooling water to flow through the system for cooling the condenser and closing which forms a the electric switch through the medium of i the hydraulic motor 71 llhen the temperature falls to a predetermined minimum, the

fluid in the thermostat will contract sufficiently to permit spring 56 to close valve 55 and shut off the flow of the water through the condenser, and also permit the electrical switch 2' to be opened and thereby cut off the flow ofcurrent to motor 72.

Vi? hen valve on controlled bv the thermo stat Z is closed, piston 45, which actuates switch 2", is in the position shown in Figs. 10 and 11, and the piston valve in cylinder 48 is in its lowered position so that cylinder 44 is open to exhaust through port 47 and pipe w. W hen thermostatic valve m is opened by the thermostat Z, water is admitted to the lower end of cylinder 48, and as the upper end is open to exhaust or waste through pipe 2., the valve member in cylinder 48 will be shifted to the position shown in Figs. .4 and Jail? 10. This shifting of this valve member will open port 47 to water pressure, which will act on piston 45 against the action of spring 47, move the piston 45 together with its stem 46, shiftlever j and close switch 2'. This closing of switch 2' will cause motor h to rotate, which will in turn actuate the compreSSor The valve 49, 50 will be retained in its elevated position as long as the thermostat valve on is open and water will be continuously passed through the system from pipe 1', through the condenser to pipe 8, to the lower end of cylinder 48, passage 51 to the upper end of said cylinder, pipe t to thermost at valve m and from thermostat valve m to waste through pipe Q0. The parts will remain in this position until the thermostat valve m is moved to its closed position and when this occurs the flow of water through the system will be cut off. As the outlet through pipe 6 is closed when the thermostat valve is closed, pressure will build up above p'iston head 49 on'difl'erential valve, and as this piston head is of greater area than piston head 50 said valve will be moved downward and open port 47 to pipe to. This opening of port 47 to pipe 01. will permit the water to escape from cylinder 44 in front of piston 45 and spring 47 will shift the piston 45 and its stem 46, thereby shifting lever j and open switch 2', and thereby cut 0d the current to motor h.

The reservoir 9 for the refrigerating fluid is provided with pet cocks for permitting the escape of air when charging the system, and also for determining the height of fluid in the reservoir.

72 is a pressure gage mounted on one face of crank case-casting 11 of the compressor, which is connected with the suction side of the compressor, preferably pipe-g as indicated in dotted lines in Fig. 2, and 73 is a similar gage at the side of gage 7 2 which is connected to the pressure side of the compressor, which is preferably connected to the chamber in the crank case, which is in connection with pressure or outlet chamber 36 .hy means of an oil return passage 74.

By varying the pressure of spring 56, the temperature at which the chamber is maintained may be varied.

By adjusting the needle valve 52, the flow of water through the system for cooling the refrigerating fluid passing through the condenser may be varied.

The advantages of my invention result from the provision of a simple, efficient, automatic refrigerating system, which is compact, and which can readily be positioned'above a household refrigerator, and in which all of the parts, except the refrigcrating coil, thermostat and the valve controlled thereby, are supported on a base member to which they are fixedly secured.

further advantage results from the provision of such a system having a hydraulic motor for actuating the switch for the electric motor whereby the current to the motor is controlled by the water for coolingv the naeavso condenser, so that the current is not turned on until water flows through the system, and is turned 0d when the fiow'of water stops. A still further advantage results from the provision of means whereby the cooling water is turned on and off by means of the thermostat in the refrigerating chamber, as well as from the provision of means for readily varying the means for turning on and off the water whereby the normal temperature in the refrigerator may be varied.

A further advantage results from the provision of means for adjusting the volume of flow of the cooling liquid (water) so that the system may be operated at the lowest cost where both water and current are me tered.

Another advantage results from the provision-of a hydraulic motor having an automatic valve which is controlled by the flow of water through the system,- whereby the actuating mechanism for the electrical switch is reduced to a minimum and in which the various elements are directly actuated by the pressure of the water.

' A still further advantage results from the provision of a particular type of condenser whereby I am enabled to provide a small condenser with a relatively long cooling surface over which the refrigerating liquid asses.

Still another advantage results from (the provision of a compressor having a plurality of pistons and a plurality of crank shafts, geared to each other so that the shafts will rotate in unison with each other, and in which the axes of the shafts are in different planes, so that single armed cranks may be used, and thereby materially cheapen the structure.

Having now fully described my invention, what it claim and desire to protect by Letters Patent is- 1. A refrigerating system having a compressor, an electric motor for driving the compressor, an electric switch for controlling the current for the electric motorfa cooling fluid supply for the system, a valve for control ling the flow of fluid through the system, a temperature actuated device fr opening and closing the. valve, a fluid pre sure actuated motor for opening and closing the switch actuated by the cooling fluid, and an automatic valve for controlling the admission of fluid to and exhaust from the pressure motor arranged to be actuated by the cooling fluid to cause the fluid pressure motor to close the electric switch when cooling fluid is passing through the system and to open the switch when the fluid control valve is closed;

2. A refrigerating system having "a compressor, an electric motor for driving the compressor, an electric switch for controlling the current for electricmotor, a cooling fill too

lllll said pressure motor nae/agree fluid supply for the system, a valve for controlling the flow of fluid through the system, a temperature actuated device directly connected to the said control valve for opening and closing the valve, a fluid pressure actuated motor for shifting the electric switch, being arranged to be actuated to close the switch when the fluid control valve is opened and to open the switch when the fluid control valve is closed, an automatic valve for controlling the admission of fluid to, and the exhaust from, the fluid pressur motor, and means connected to' the automatic valve to cause the cooling fluid to shift the automatic valve in one direction when the control valve is closed and to shift the automatic valve in the other direction when the control valve is opened.

3'. A refrigerating system having a continuous refrigerating fluid circuit includin a compressor, an electric motor for driving the compressor, an electric circuit including the electric motor, a switch in the electric circuit for controlling the current for the motor, a cooling fluid circuit for cooling the refrigerating circuit, a control valve'for controlling the flow of fluid through the cooling circuit, a thermostat for opening and closing the control valve, a fluid pressure motor for-actuating the switch in one direction, a spring for actuating the switch in the other direction, an automatic valve in the cooling circuit for controlling the admission of fluid to the pressure motor from the cooling circuitand exhaust from the pressure motor to back of the cooling circuit, and means connected to said automatic valve for shiftingsaid automatic valve in one direction when the control valve is open and for shifting the automatic valve in the other direction when the control valve is closed.

4. A refrigerating system. having a refrigerating fluid circuit, an absorbing fluid circuit connected to a constant supply, a motor driven compressor for the refrigerating circuit, a power control device for the motor, a pressure motor connected to the absorbing circuit for actuating the power control device, an automatic valve for the pressure motor and arranged to be moved in one direction when fluid is flowing through the circuit and to be moved in the reverse direction when the flow of fluid is cut ofl, and a thermostatically controlled valve for the absorbing circuit.

5. A refrigerating system having a refrigerating fluid circuit, an absorbing fluid circuit connected to a constant supply, a motor driven compressor for the refrigerating circuit, a power control device for the motor, a pressure motor connected to the absorbing circuit, said pressure motor having a cylinder, a piston in the cylinder connected to the power control device and arranged to be moved in one direction by the pressure in the absorbing circuit, a spring for moving the piston in the other direction, an automatic valve for controlling the flow to and from the cylinder, said valve being arranged to open the cylinder to pressure when fluid is passing through the absorbing circuit and to open the cylinder to exhaust when the flow through said circuit is shut off, and a thermostatically controlled valve for controlling the outlet from the absorbing circuit.

6. A refrigerating having a re frigerating circuit through which refrigerating fluid is passed, a cooling circuit through which cooling fluid is passed for cooling a portion of the refrigerating cir- 'cuit, a compressor in the refrigerating circuit, an electric motor for driving the compressor, an electric switch for the electric vmotor, an electric circuit including the electric motor and switch, a control valve for controlling the flow of fluid through the cooling system, a thermostat for opening and closing the control valve, hydraulic means, including a differential piston, for shifting the switch included in the cooling circuit, there being a by-pass connecting the opposite sides of said piston to each other, and an adjustable valve for said by-pass, the arrangement being such that when the control valve is open the pressure on the larger area of the piston is reduced to shift the piston in one direction, and when the control valve is closed the pressure on both sides of the piston is equal so that the pistonis shifted in the other direction.

In testimony of which invention, I have hereunto set m hand, art Birmingham, on this 21st day or August, 1922.

RUBERT A. BURFQRD, J 

